Companies who are already involved in concrete recycling are very interested in the reCO2ver® technology. It not only simplifies concrete recycling, but also makes it more economically viable and sustainable.

What distinguishes reCO2ver® from other concrete recycling processes?

With conventional concrete recycling, the old concrete is broken up into pieces of varying sizes of up to a diameter of 32 millimeters. These fragments are used as aggregate for new concrete. This has many drawbacks, as these fragments have a greater surface area and a higher porosity than aggregates from primary rock. With the reCO2ver® procedure, the fragments are broken down into their component parts, namely the stones and the cement stone powder. In addition, the cement stone powder reacts with the CO2 (carbonation) and binds it to the powder.

"Our findings so far have been extremely positive." Carsten Rieger, Sika Zurich, Switzerland
 Corporate Market Development Manager Target Market Concrete, Sika, Zurich
Image: Carsten Rieger, Corporate Market Development Manager Target Market Concrete, Sika, Zurich
What is Sika doing to promote the construction of larger, more commercially viable facilities after successfully completing the pilot plant?

Sika is first carrying out trials in the pilot facility to optimize both the process and the facility. The plan is also to work with customer-specific material in order to emphasize the benefits for customers. The results will then be incorporated into the design for larger facilities.

Will emerging market countries be able to afford such facilities, too, or will they remain reserved for developed nations?

These facilities will be of interest wherever a market for recycling concrete exists, and wherever an infrastructure exists for the sorting and breaking- up of concrete waste. At the moment, this is true of developed countries first and foremost. But as soon as incentives for concrete recycling are put in place in emerging markets and a market thus develops, reCO2ver® facilities will make commercial sense there too. The investment in the facility must be set against the added value it provides. That lies in the value of the reclaimed material and indirectly from the CO2 bound in the material.


What is the commercial interest of the company in the dissemination of this reCO2ver® technology?

Sika’s aim with this technology is to reduce CO2 emissions in the construction industry. What’s more, Sika owns the process patent, and is therefore entitled to license the process. Further opportunities will result from the use of additives to increase the quality of the reclaimed materials and from the sale of CO2 certificates.

What’s special about the Sika additives used in the reCO2ver® procedure?

The corresponding Sika additives are still in the development phase. The aim is to develop additives that enhance the quality of the reclaimed powder and further optimize its performance as a cement substitute.

What kind of potential do you see for the sale of these additives?

We’ll have to see. But we are currently anticipating potential of CHF 90 million a year. 

When will the pilot phase be concluded – i.e. when will reCO2ver be officially launched?

The pilot phase will be concluded in the first half of 2022. Our findings so far have been extremely positive.

The innovative reCO2ver® recycling process enables a circular economy for concrete and the market to produce new, high-performance concrete from concrete waste.
The Sika reCO2ver® pilot facility as installed at Eberhard Unternehmungen in Switzerland.
The Sika reCO2ver® pilot facility as installed at Eberhard Unternehmungen in Switzerland.
What kind of reception do you expect for concrete recycling and the use of recycled concrete? Have you already received feedback from the industry?

The companies who are already involved in concrete recycling are very interested in the reCO2ver technology, as it will greatly simplify concrete recycling, as well as making it more economically viable and sustainable. What we see is concrete recycling being introduced wherever there is a political commitment to it and the corresponding regulatory parameters have been put in place. 

So you think political incentives or regulations are required to promote concrete recycling? 

There are already regulations in place for reducing CO2 emissions, and the reCO2ver technology is one of few procedures that “sequesters” – or binds – CO2. This is in the interests of all stakeholder groups. Regulations that promote concrete recycling in a targeted way would therefore make sense in our view.

What sort of a figure would you put on the market potential for reCO2ver®?

In Europe alone, some 300 million tons of concrete waste are produced every year. Globally we reckon this volume is in the region of 600 million tons per year. We estimate the global market that Sika can reach within the next two to five years to be around five percent of that figure. So for the time being that would equate to 30 million tons of concrete waste.